drivers/regulator/helpers.c

   1 /*
   2  * helpers.c  --  Voltage/Current Regulator framework helper functions.
   3  *
   4  * Copyright 2007, 2008 Wolfson Microelectronics PLC.
   5  * Copyright 2008 SlimLogic Ltd.
   6  *
   7  *  This program is free software; you can redistribute  it and/or modify it
   8  *  under  the terms of  the GNU General  Public License as published by the
   9  *  Free Software Foundation;  either version 2 of the  License, or (at your
  10  *  option) any later version.
  11  *
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/err.h>
  16 #include <linux/delay.h>
  17 #include <linux/regmap.h>
  18 #include <linux/regulator/consumer.h>
  19 #include <linux/regulator/driver.h>
  20 #include <linux/module.h>
  21
  22 /**
  23  * regulator_is_enabled_regmap - standard is_enabled() for regmap users
  24  *
  25  * @rdev: regulator to operate on
  26  *
  27  * Regulators that use regmap for their register I/O can set the
  28  * enable_reg and enable_mask fields in their descriptor and then use
  29  * this as their is_enabled operation, saving some code.
  30  */
  31 int regulator_is_enabled_regmap(struct regulator_dev *rdev)
  32 {
  33         unsigned int val;
  34         int ret;
  35
  36         ret = regmap_read(rdev->regmap, rdev->desc->enable_reg, &val);
  37         if (ret != 0)
  38                 return ret;
  39
  40         if (rdev->desc->enable_is_inverted)
  41                 return (val & rdev->desc->enable_mask) == 0;
  42         else
  43                 return (val & rdev->desc->enable_mask) != 0;
  44 }
  45 EXPORT_SYMBOL_GPL(regulator_is_enabled_regmap);
  46
  47 /**
  48  * regulator_enable_regmap - standard enable() for regmap users
  49  *
  50  * @rdev: regulator to operate on
  51  *
  52  * Regulators that use regmap for their register I/O can set the
  53  * enable_reg and enable_mask fields in their descriptor and then use
  54  * this as their enable() operation, saving some code.
  55  */
  56 int regulator_enable_regmap(struct regulator_dev *rdev)
  57 {
  58         unsigned int val;
  59
  60         if (rdev->desc->enable_is_inverted)
  61                 val = 0;
  62         else
  63                 val = rdev->desc->enable_mask;
  64
  65         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  66                                   rdev->desc->enable_mask, val);
  67 }
  68 EXPORT_SYMBOL_GPL(regulator_enable_regmap);
  69
  70 /**
  71  * regulator_disable_regmap - standard disable() for regmap users
  72  *
  73  * @rdev: regulator to operate on
  74  *
  75  * Regulators that use regmap for their register I/O can set the
  76  * enable_reg and enable_mask fields in their descriptor and then use
  77  * this as their disable() operation, saving some code.
  78  */
  79 int regulator_disable_regmap(struct regulator_dev *rdev)
  80 {
  81         unsigned int val;
  82
  83         if (rdev->desc->enable_is_inverted)
  84                 val = rdev->desc->enable_mask;
  85         else
  86                 val = 0;
  87
  88         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
  89                                   rdev->desc->enable_mask, val);
  90 }
  91 EXPORT_SYMBOL_GPL(regulator_disable_regmap);
  92
  93 /**
  94  * regulator_get_voltage_sel_regmap - standard get_voltage_sel for regmap users
  95  *
  96  * @rdev: regulator to operate on
  97  *
  98  * Regulators that use regmap for their register I/O can set the
  99  * vsel_reg and vsel_mask fields in their descriptor and then use this
 100  * as their get_voltage_vsel operation, saving some code.
 101  */
 102 int regulator_get_voltage_sel_regmap(struct regulator_dev *rdev)
 103 {
 104         unsigned int val;
 105         int ret;
 106
 107         ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
 108         if (ret != 0)
 109                 return ret;
 110
 111         val &= rdev->desc->vsel_mask;
 112         val >>= ffs(rdev->desc->vsel_mask) - 1;
 113
 114         return val;
 115 }
 116 EXPORT_SYMBOL_GPL(regulator_get_voltage_sel_regmap);
 117
 118 /**
 119  * regulator_set_voltage_sel_regmap - standard set_voltage_sel for regmap users
 120  *
 121  * @rdev: regulator to operate on
 122  * @sel: Selector to set
 123  *
 124  * Regulators that use regmap for their register I/O can set the
 125  * vsel_reg and vsel_mask fields in their descriptor and then use this
 126  * as their set_voltage_vsel operation, saving some code.
 127  */
 128 int regulator_set_voltage_sel_regmap(struct regulator_dev *rdev, unsigned sel)
 129 {
 130         int ret;
 131
 132         sel <<= ffs(rdev->desc->vsel_mask) - 1;
 133
 134         ret = regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg,
 135                                   rdev->desc->vsel_mask, sel);
 136         if (ret)
 137                 return ret;
 138
 139         if (rdev->desc->apply_bit)
 140                 ret = regmap_update_bits(rdev->regmap, rdev->desc->apply_reg,
 141                                          rdev->desc->apply_bit,
 142                                          rdev->desc->apply_bit);
 143         return ret;
 144 }
 145 EXPORT_SYMBOL_GPL(regulator_set_voltage_sel_regmap);
 146
 147 /**
 148  * regulator_map_voltage_iterate - map_voltage() based on list_voltage()
 149  *
 150  * @rdev: Regulator to operate on
 151  * @min_uV: Lower bound for voltage
 152  * @max_uV: Upper bound for voltage
 153  *
 154  * Drivers implementing set_voltage_sel() and list_voltage() can use
 155  * this as their map_voltage() operation.  It will find a suitable
 156  * voltage by calling list_voltage() until it gets something in bounds
 157  * for the requested voltages.
 158  */
 159 int regulator_map_voltage_iterate(struct regulator_dev *rdev,
 160                                   int min_uV, int max_uV)
 161 {
 162         int best_val = INT_MAX;
 163         int selector = 0;
 164         int i, ret;
 165
 166         /* Find the smallest voltage that falls within the specified
 167          * range.
 168          */
 169         for (i = 0; i < rdev->desc->n_voltages; i++) {
 170                 ret = rdev->desc->ops->list_voltage(rdev, i);
 171                 if (ret < 0)
 172                         continue;
 173
 174                 if (ret < best_val && ret >= min_uV && ret <= max_uV) {
 175                         best_val = ret;
 176                         selector = i;
 177                 }
 178         }
 179
 180         if (best_val != INT_MAX)
 181                 return selector;
 182         else
 183                 return -EINVAL;
 184 }
 185 EXPORT_SYMBOL_GPL(regulator_map_voltage_iterate);
 186
 187 /**
 188  * regulator_map_voltage_ascend - map_voltage() for ascendant voltage list
 189  *
 190  * @rdev: Regulator to operate on
 191  * @min_uV: Lower bound for voltage
 192  * @max_uV: Upper bound for voltage
 193  *
 194  * Drivers that have ascendant voltage list can use this as their
 195  * map_voltage() operation.
 196  */
 197 int regulator_map_voltage_ascend(struct regulator_dev *rdev,
 198                                  int min_uV, int max_uV)
 199 {
 200         int i, ret;
 201
 202         for (i = 0; i < rdev->desc->n_voltages; i++) {
 203                 ret = rdev->desc->ops->list_voltage(rdev, i);
 204                 if (ret < 0)
 205                         continue;
 206
 207                 if (ret > max_uV)
 208                         break;
 209
 210                 if (ret >= min_uV && ret <= max_uV)
 211                         return i;
 212         }
 213
 214         return -EINVAL;
 215 }
 216 EXPORT_SYMBOL_GPL(regulator_map_voltage_ascend);
 217
 218 /**
 219  * regulator_map_voltage_linear - map_voltage() for simple linear mappings
 220  *
 221  * @rdev: Regulator to operate on
 222  * @min_uV: Lower bound for voltage
 223  * @max_uV: Upper bound for voltage
 224  *
 225  * Drivers providing min_uV and uV_step in their regulator_desc can
 226  * use this as their map_voltage() operation.
 227  */
 228 int regulator_map_voltage_linear(struct regulator_dev *rdev,
 229                                  int min_uV, int max_uV)
 230 {
 231         int ret, voltage;
 232
 233         /* Allow uV_step to be 0 for fixed voltage */
 234         if (rdev->desc->n_voltages == 1 && rdev->desc->uV_step == 0) {
 235                 if (min_uV <= rdev->desc->min_uV && rdev->desc->min_uV <= max_uV)
 236                         return 0;
 237                 else
 238                         return -EINVAL;
 239         }
 240
 241         if (!rdev->desc->uV_step) {
 242                 BUG_ON(!rdev->desc->uV_step);
 243                 return -EINVAL;
 244         }
 245
 246         if (min_uV < rdev->desc->min_uV)
 247                 min_uV = rdev->desc->min_uV;
 248
 249         ret = DIV_ROUND_UP(min_uV - rdev->desc->min_uV, rdev->desc->uV_step);
 250         if (ret < 0)
 251                 return ret;
 252
 253         ret += rdev->desc->linear_min_sel;
 254
 255         /* Map back into a voltage to verify we're still in bounds */
 256         voltage = rdev->desc->ops->list_voltage(rdev, ret);
 257         if (voltage < min_uV || voltage > max_uV)
 258                 return -EINVAL;
 259
 260         return ret;
 261 }
 262 EXPORT_SYMBOL_GPL(regulator_map_voltage_linear);
 263
 264 /**
 265  * regulator_map_voltage_linear - map_voltage() for multiple linear ranges
 266  *
 267  * @rdev: Regulator to operate on
 268  * @min_uV: Lower bound for voltage
 269  * @max_uV: Upper bound for voltage
 270  *
 271  * Drivers providing linear_ranges in their descriptor can use this as
 272  * their map_voltage() callback.
 273  */
 274 int regulator_map_voltage_linear_range(struct regulator_dev *rdev,
 275                                        int min_uV, int max_uV)
 276 {
 277         const struct regulator_linear_range *range;
 278         int ret = -EINVAL;
 279         int voltage, i;
 280
 281         if (!rdev->desc->n_linear_ranges) {
 282                 BUG_ON(!rdev->desc->n_linear_ranges);
 283                 return -EINVAL;
 284         }
 285
 286         for (i = 0; i < rdev->desc->n_linear_ranges; i++) {
 287                 int linear_max_uV;
 288
 289                 range = &rdev->desc->linear_ranges[i];
 290                 linear_max_uV = range->min_uV +
 291                         (range->max_sel - range->min_sel) * range->uV_step;
 292
 293                 if (!(min_uV <= linear_max_uV && max_uV >= range->min_uV))
 294                         continue;
 295
 296                 if (min_uV <= range->min_uV)
 297                         min_uV = range->min_uV;
 298
 299                 /* range->uV_step == 0 means fixed voltage range */
 300                 if (range->uV_step == 0) {
 301                         ret = 0;
 302                 } else {
 303                         ret = DIV_ROUND_UP(min_uV - range->min_uV,
 304                                            range->uV_step);
 305                         if (ret < 0)
 306                                 return ret;
 307                 }
 308
 309                 ret += range->min_sel;
 310
 311                 break;
 312         }
 313
 314         if (i == rdev->desc->n_linear_ranges)
 315                 return -EINVAL;
 316
 317         /* Map back into a voltage to verify we're still in bounds */
 318         voltage = rdev->desc->ops->list_voltage(rdev, ret);
 319         if (voltage < min_uV || voltage > max_uV)
 320                 return -EINVAL;
 321
 322         return ret;
 323 }
 324 EXPORT_SYMBOL_GPL(regulator_map_voltage_linear_range);
 325
 326 /**
 327  * regulator_list_voltage_linear - List voltages with simple calculation
 328  *
 329  * @rdev: Regulator device
 330  * @selector: Selector to convert into a voltage
 331  *
 332  * Regulators with a simple linear mapping between voltages and
 333  * selectors can set min_uV and uV_step in the regulator descriptor
 334  * and then use this function as their list_voltage() operation,
 335  */
 336 int regulator_list_voltage_linear(struct regulator_dev *rdev,
 337                                   unsigned int selector)
 338 {
 339         if (selector >= rdev->desc->n_voltages)
 340                 return -EINVAL;
 341         if (selector < rdev->desc->linear_min_sel)
 342                 return 0;
 343
 344         selector -= rdev->desc->linear_min_sel;
 345
 346         return rdev->desc->min_uV + (rdev->desc->uV_step * selector);
 347 }
 348 EXPORT_SYMBOL_GPL(regulator_list_voltage_linear);
 349
 350 /**
 351  * regulator_list_voltage_linear_range - List voltages for linear ranges
 352  *
 353  * @rdev: Regulator device
 354  * @selector: Selector to convert into a voltage
 355  *
 356  * Regulators with a series of simple linear mappings between voltages
 357  * and selectors can set linear_ranges in the regulator descriptor and
 358  * then use this function as their list_voltage() operation,
 359  */
 360 int regulator_list_voltage_linear_range(struct regulator_dev *rdev,
 361                                         unsigned int selector)
 362 {
 363         const struct regulator_linear_range *range;
 364         int i;
 365
 366         if (!rdev->desc->n_linear_ranges) {
 367                 BUG_ON(!rdev->desc->n_linear_ranges);
 368                 return -EINVAL;
 369         }
 370
 371         for (i = 0; i < rdev->desc->n_linear_ranges; i++) {
 372                 range = &rdev->desc->linear_ranges[i];
 373
 374                 if (!(selector >= range->min_sel &&
 375                       selector <= range->max_sel))
 376                         continue;
 377
 378                 selector -= range->min_sel;
 379
 380                 return range->min_uV + (range->uV_step * selector);
 381         }
 382
 383         return -EINVAL;
 384 }
 385 EXPORT_SYMBOL_GPL(regulator_list_voltage_linear_range);
 386
 387 /**
 388  * regulator_list_voltage_table - List voltages with table based mapping
 389  *
 390  * @rdev: Regulator device
 391  * @selector: Selector to convert into a voltage
 392  *
 393  * Regulators with table based mapping between voltages and
 394  * selectors can set volt_table in the regulator descriptor
 395  * and then use this function as their list_voltage() operation.
 396  */
 397 int regulator_list_voltage_table(struct regulator_dev *rdev,
 398                                  unsigned int selector)
 399 {
 400         if (!rdev->desc->volt_table) {
 401                 BUG_ON(!rdev->desc->volt_table);
 402                 return -EINVAL;
 403         }
 404
 405         if (selector >= rdev->desc->n_voltages)
 406                 return -EINVAL;
 407
 408         return rdev->desc->volt_table[selector];
 409 }
 410 EXPORT_SYMBOL_GPL(regulator_list_voltage_table);
 411
 412 /**
 413  * regulator_set_bypass_regmap - Default set_bypass() using regmap
 414  *
 415  * @rdev: device to operate on.
 416  * @enable: state to set.
 417  */
 418 int regulator_set_bypass_regmap(struct regulator_dev *rdev, bool enable)
 419 {
 420         unsigned int val;
 421
 422         if (enable)
 423                 val = rdev->desc->bypass_mask;
 424         else
 425                 val = 0;
 426
 427         return regmap_update_bits(rdev->regmap, rdev->desc->bypass_reg,
 428                                   rdev->desc->bypass_mask, val);
 429 }
 430 EXPORT_SYMBOL_GPL(regulator_set_bypass_regmap);
 431
 432 /**
 433  * regulator_get_bypass_regmap - Default get_bypass() using regmap
 434  *
 435  * @rdev: device to operate on.
 436  * @enable: current state.
 437  */
 438 int regulator_get_bypass_regmap(struct regulator_dev *rdev, bool *enable)
 439 {
 440         unsigned int val;
 441         int ret;
 442
 443         ret = regmap_read(rdev->regmap, rdev->desc->bypass_reg, &val);
 444         if (ret != 0)
 445                 return ret;
 446
 447         *enable = val & rdev->desc->bypass_mask;
 448
 449         return 0;
 450 }
 451 EXPORT_SYMBOL_GPL(regulator_get_bypass_regmap);